Grievous Gladiator's Mooncloth Robe is part of the transmog set Grievous Gladiator's Satin Armor (Priest only), which the Appearances collection lists in 2 versions. The other 13 pieces:
Built from the World of Warcraft client build files and recorded Auction House snapshots.
Where Grievous Gladiator's Mooncloth Robe Fits
Other Items Named Grievous Gladiator's Mooncloth Robe
4 other items in the current build are also called Grievous Gladiator's Mooncloth Robe. Same-name entries are usually a different rank, faction, quest stage or reward track of the same object.
Items Numbered Next to Grievous Gladiator's Mooncloth Robe
Blizzard numbers items as they are created, so the named items next to ID 100412 (100407 to 100417) were usually added in the same batch as Grievous Gladiator's Mooncloth Robe: the same quest line, zone, vendor or reward set.